I've not been paying attention to the pouch discussion, but the subject
of egg white caught my eye.  Somebody needs to post a warning...

Like most animal matter, raw egg white will eventually decay and
it can also attract pests.  Ever wonder why mice and insects take
up residence inside of pipe organs?  Leather, hide glue, etc. --
a veritable smorgasbord of feasting opportunities.  Mix in some egg
white and you're certain to have chewed pouch leather in no time.
I guess that keeps the restoration guys employed.

Starch is the property of egg whites that makes them so commonly used
in applications both musical and culinary.  In this case it would be
better to use a synthetic starch or a processed starch -- the results
are surely as good but the longevity of the material is much better.

If you feel a strong compulsion to use eggs, be sure to separate the
whites and yolks carefully as all of the bad fat and cholesterol is
in the yolk.  Keep your organ healthy!

Steve Matta